(BQ) Part 1 book General, organic, and biological chemistry has contents: Basic concepts about matter, measurements in chemistry, atomic structure and the periodic table, chemical bonding the covalent bond model, chemical calculations formula masses, moles, and chemical equations,...and other contents.
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Trang 4General, Organic, and Biological Chemistry
F I F T H E D I T I O N
H STEPHEN STOKER
Weber State University
Australia • Brazil • Japan • Korea • Mexico • Singapore • Spain • United Kingdom • United States
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Trang 5© 2010 Brooks/Cole, Cengage Learning ALL RIGHTS RESERVED No part of this work covered by the copyright herein may be reproduced, transmitted, stored, or used in any form or by any means graphic, electronic, or mechanical, including but not limited to photocopying, recording, scanning, digitizing, taping, Web distribution, information networks,
or information storage and retrieval systems, except as permitted under Section 107 or 108 of the 1976 United States Copyright Act, without the prior written permission of the publisher.
General, Organic, and Biological Chemistry, Fifth
Edition
H Stephen Stoker
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Student Edition ISBN-13: 978-0-547-15281-3 ISBN-10: 0-547-15281-7
International Student Edition:
ISBN-13: 978-0-495-83146-4 ISBN-10: 0-495-83146-8 2880T_fm_i-xxviii.indd Page iv 11/5/08 1:06:52 AM user-s131 /Volumes/MHSF/MH-SANFRAN/MHSF027/MHS
Trang 6Brief Contents
Preface xiv
Chapter 2 Measurements in Chemistry 22Chapter 3 Atomic Structure and the Periodic Table 51Chapter 4 Chemical Bonding: The Ionic Bond Model 83Chapter 5 Chemical Bonding: The Covalent Bond Model 108Chapter 6 Chemical Calculations: Formula Masses, Moles, and Chemical
Equations 137Chapter 7 Gases, Liquids and Solids 163Chapter 8 Solutions 192
Chapter 9 Chemical Reactions 223Chapter 10 Acids, Bases, and Salts 253Chapter 11 Nuclear Chemistry 292
Chapter 12 Saturated Hydrocarbons 321Chapter 13 Unsaturated Hydrocarbons 361Chapter 14 Alcohols, Phenols, and Ethers 399Chapter 15 Aldehydes and Ketones 442Chapter 16 Carboxylic Acids, Esters, and Other Acid Derivatives 473
Chapter 23 Biochemical Energy Production 777Chapter 24 Carbohydrate Metabolism 811Chapter 25 Lipid Metabolism 842
Chapter 26 Protein Metabolism 875
Answers to Selected Exercises A-1Photo Credits A-26
Index/Glossary A-27
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Trang 8Preface xiv
PA RT I G E N E RA L C H E M I ST RY
Chapter 1 Basic Concepts About Matter 1
1.1 Chemistry: The Study of Matter 1
1.2 Physical States of Matter 2
1.3 Properties of Matter 2
1.4 Changes in Matter 4
CHEMISTRY AT A GLANCE Use of the Terms Physical and
Chemical 5 1.5 Pure Substances and Mixtures 6
1.6 Elements and Compounds 7
CHEMISTRY AT A GLANCE Classes of Matter 8
1.7 Discovery and Abundance of the Elements 9
1.8 Names and Chemical Symbols of the Elements 11
1.9 Atoms and Molecules 12
2.2 Metric System Units 23
2.3 Exact and Inexact Numbers 26
2.4 Uncertainty in Measurement and Signifi cant
Figures 26 CHEMISTRY AT A GLANCE Signifi cant Figures 28
2.5 Signifi cant Figures and Mathematical
Operations 28 2.6 Scientifi c Notation 32
3.1 Internal Structure of an Atom 51
3.2 Atomic Number and Mass Number 53 3.3 Isotopes and Atomic Masses 55 CHEMISTRY AT A GLANCE Atomic Structure 58 3.4 The Periodic Law and the Periodic Table 59 3.5 Metals and Nonmetals 62
3.6 Electron Arrangements Within Atoms 63 CHEMISTRY AT A GLANCE Shell–Subshell–Orbital Interrelationships 67
3.7 Electron Confi gurations and Orbital Diagrams 67 3.8 The Electronic Basis for the Periodic Law and the Periodic Table 71
3.9 Classifi cation of the Elements 73 CHEMISTRY AT A GLANCE Element Classifi cation Schemes and the Periodic Table 75
CHEMICAL CONNECTIONS Protium, Deuterium, and Tritium: The Three Isotopes of Hydrogen 55
Metallic Elements and the Human Body 64 Iron: The Most Abundant Transition Element in the Human Body 74Chapter 4 Chemical Bonding: The Ionic
Bond Model 83
4.1 Chemical Bonds 83 4.2 Valence Electrons and Lewis Symbols 84 4.3 The Octet Rule 86
4.4 The Ionic Bond Model 87 4.5 The Sign and Magnitude of Ionic Charge 89 4.6 Lewis Structures for Ionic Compounds 91 4.7 Chemical Formulas for Ionic Compounds 92 4.8 The Structure of Ionic Compounds 93 4.9 Recognizing and Naming Binary Ionic Compounds 94
CHEMISTRY AT A GLANCE Ionic Bonds and Ionic Compounds 95
4.10 Polyatomic Ions 98 4.11 Chemical Formulas and Names for Ionic Compounds Containing Polyatomic Ions 100
CHEMISTRY AT A GLANCE Nomenclature of Ionic Compounds 102
CHEMICAL CONNECTIONS Fresh Water, Seawater, Hard Water, and Soft Water: A Matter
of Ions 90 Tooth Enamel: A Combination of Monatomic and Polyatomic Ions 100
Chapter 5 Chemical Bonding: The Covalent
Trang 95.3 Single, Double, and Triple Covalent Bonds 111
5.4 Valence Electrons and Number of Covalent Bonds
Formed 112
5.5 Coordinate Covalent Bonds 113
5.6 Systematic Procedures for Drawing Lewis
The Chemical Senses of Smell and Taste 122
Chapter 6 Chemical Calculations: Formula
Masses, Moles, and Chemical Equations 137
6.1 Formula Masses 137
6.2 The Mole: A Counting Unit for Chemists 138
6.3 The Mass of a Mole 140
6.4 Chemical Formulas and the Mole Concept 142
6.5 The Mole and Chemical Calculations 143
6.6 Writing and Balancing Chemical Equations 146
6.7 Chemical Equations and the Mole Concept 150
CHEMISTRY AT A GLANCE Relationships Involving the Mole
Concept 151
6.8 Chemical Calculations Using Chemical
Equations 151
CHEMICAL CONNECTIONS
Carbon Monoxide Air Pollution: A Case of Combining Ratios 153
Chemical Reactions on an Industrial Scale: Sulfuric Acid 156
Chapter 7 Gases, Liquids, and Solids 163
7.1 The Kinetic Molecular Theory of Matter 163
7.2 Kinetic Molecular Theory and Physical States 165
7.3 Gas Law Variables 167
7.4 Boyle’s Law: A Pressure-Volume Relationship 168
7.5 Charles’s Law: A Temperature-Volume
Relationship 170
7.6 The Combined Gas Law 172
7.7 The Ideal Gas Law 172
7.8 Dalton’s Law of Partial Pressures 173
CHEMISTRY AT A GLANCE The Gas Laws 175
7.9 Changes of State 176
7.10 Evaporation of Liquids 177
7.11 Vapor Pressure of Liquids 177 7.12 Boiling and Boiling Point 180 7.13 Intermolecular Forces in Liquids 181 CHEMISTRY AT A GLANCE Intermolecular Forces 185 CHEMICAL CONNECTIONS
The Importance of Gas Densities 167 Blood Pressure and the Sodium Ion/Potassium Ion Ratio 178 Hydrogen Bonding and the Density of Water 184
viii Contents
Chapter 8 Solutions 192
8.1 Characteristics of Solutions 192 8.2 Solubility 193
8.3 Solution Formation 196 8.4 Solubility Rules 197 8.5 Solution Concentration Units 198 8.6 Dilution 205
CHEMISTRY AT A GLANCE Solutions 207 8.7 Colloidal Dispersions and Suspensions 208 8.8 Colligative Properties of Solutions 209 8.9 Osmosis and Osmotic Pressure 210 CHEMISTRY AT A GLANCE Summary of Colligative Property Terminology 215
8.10 Dialysis 215 CHEMICAL CONNECTIONS Factors Affecting Gas Solubility 195 Solubility of Vitamins 199 Controlled-Release Drugs: Regulating Concentration, Rate, and Location of Release 206
The Artifi cial Kidney: A Hemodialysis Machine 216
Chapter 9 Chemical Reactions 223
9.1 Types of Chemical Reactions 223 9.2 Redox and Nonredox Chemical Reactions 226 CHEMISTRY AT A GLANCE Types of Chemical
Reactions 228
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Trang 109.3 Terminology Associated with Redox
Processes 230 9.4 Collision Theory and Chemical Reactions 233
9.5 Exothermic and Endothermic Chemical
Reactions 234 9.6 Factors That Infl uence Chemical Reaction
Rates 235 9.7 Chemical Equilibrium 237
CHEMISTRY AT A GLANCE Factors That Increase Reaction
Rates 238 9.8 Equilibrium Constants 239
9.9 Altering Equilibrium Conditions: Le Châtelier’s
Principle 243 CHEMICAL CONNECTIONS
Combustion Reactions, Carbon Dioxide, and Global Warming 227
“Undesirable” Oxidation–Reduction Processes: Metallic Corrosion 232
Stratospheric Ozone: An Equilibrium Situation 240
Chapter 10 Acids, Bases, and Salts 253
10.1 Arrhenius Acid–Base Theory 253
10.2 Brønsted–Lowry Acid–Base Theory 254
10.3 Mono-, Di-, and Triprotic Acids 257
CHEMISTRY AT A GLANCE Acid–Base Defi nitions 258
10.4 Strengths of Acids and Bases 258
10.5 Ionization Constants for Acids and Bases 260
10.6 Salts 261
10.7 Acid–Base Neutralization Chemical Reactions 262
10.8 Self-Ionization of Water 263
10.9 The pH Concept 266
10.10 The pKa Method for Expressing Acid Strength 269
10.11 The pH of Aqueous Salt Solutions 270
CHEMISTRY AT A GLANCE Acids and Acidic
Solutions 271 10.12 Buffers 274
10.13 The Henderson–Hasselbalch Equation 277
CHEMISTRY AT A GLANCE Buffer Systems 278
10.14 Electrolytes 278
10.15 Equivalents and Milliequivalents of
Electrolytes 280 10.16 Acid–Base Titrations 282
Chapter 11 Nuclear Chemistry 292
11.1 Stable and Unstable Nuclides 292
11.2 The Nature of Radioactive Emissions 293
11.3 Equations for Radioactive Decay 295 11.4 Rate of Radioactive Decay 297 CHEMISTRY AT A GLANCE Radioactive Decay 299 11.5 Transmutation and Bombardment Reactions 300 11.6 Radioactive Decay Series 302
11.7 Chemical Effects of Radiation 302 11.8 Biochemical Effects of Radiation 305 11.9 Detection of Radiation 306
11.10 Sources of Radiation Exposure 307 11.11 Nuclear Medicine 309
11.12 Nuclear Fission and Nuclear Fusion 312 CHEMISTRY AT A GLANCE Characteristics of Nuclear Reactions 315
11.13 Nuclear and Chemical Reactions Compared 316 CHEMICAL CONNECTIONS
Tobacco Radioactivity and the Uranium-238 Decay Series 303 Preserving Food Through Food Irradiation 307
The Indoor Radon-222 Problem 309
Chapter 12 Saturated Hydrocarbons 321
12.1 Organic and Inorganic Compounds 321 12.2 Bonding Characteristics of the Carbon Atom 322 12.3 Hydrocarbons and Hydrocarbon Derivatives 322 12.4 Alkanes: Acyclic Saturated Hydrocarbons 323 12.5 Structural Formulas 324
12.6 Alkane Isomerism 326 12.7 Conformations of Alkanes 327 12.8 IUPAC Nomenclature for Alkanes 329 12.9 Line-Angle Structural Formulas for Alkanes 335 CHEMISTRY AT A GLANCE Structural Representations for Alkane Molecules 338
12.10 Classifi cation of Carbon Atoms 338 12.11 Branched-Chain Alkyl Groups 339 12.12 Cycloalkanes 340
12.13 IUPAC Nomenclature for Cycloalkanes 341 12.14 Isomerism in Cycloalkanes 342
12.15 Sources of Alkanes and Cycloalkanes 344 12.16 Physical Properties of Alkanes
and Cycloalkanes 346 12.17 Chemical Properties of Alkanes and Cycloalkanes 347 CHEMISTRY AT A GLANCE Properties of Alkanes and Cycloalkanes 349
12.18 Nomenclature and Properties of Halogenated Alkanes 350
CHEMICAL CONNECTIONS The Occurrence of Methane 325 The Physiological Effects of Alkanes 348 Chlorofl uorocarbons and the Ozone Layer 351
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Trang 11Chapter 13 Unsaturated
Hydrocarbons 361
13.1 Unsaturated Hydrocarbons 361
13.2 Characteristics of Alkenes and Cycloalkenes 362
13.3 IUPAC Nomenclature for Alkenes and
Cycloalkenes 363
13.4 Line-Angle Structural Formulas for Alkenes 365
13.5 Constitutional Isomerism in Alkenes 366
13.6 Cis–Trans Isomerism in Alkenes 368
13.7 Naturally Occurring Alkenes 370
13.8 Physical Properties of Alkenes and
Cycloalkenes 373
13.9 Chemical Reactions of Alkenes 373
13.10 Polymerization of Alkenes: Addition
Polymers 378
13.11 Alkynes 382
CHEMISTRY AT A GLANCE Chemical Reactions
of Alkenes 383
CHEMISTRY AT A GLANCE IUPAC Nomenclature for
Alkanes, Alkenes, and Alkynes 384
13.12 Aromatic Hydrocarbons 384
13.13 Names for Aromatic Hydrocarbons 386
13.14 Aromatic Hydrocarbons: Physical Properties
Cis–Trans Isomerism and Vision 371
Carotenoids: A Source of Color 374
Fused-Ring Aromatic Hydrocarbons and Cancer 391
Chapter 14 Alcohols, Phenols,
and Ethers 399
14.1 Bonding Characteristics of Oxygen Atoms in Organic
Compounds 399
14.2 Structural Characteristics of Alcohols 400
14.3 Nomenclature for Alcohols 401
14.4 Isomerism for Alcohols 403
14.5 Important Commonly Encountered Alcohols 403
14.6 Physical Properties of Alcohols 407
14.7 Preparation of Alcohols 410
14.8 Classifi cation of Alcohols 410
14.9 Chemical Reactions of Alcohols 411
CHEMISTRY AT A GLANCE Summary of Chemical Reactions
Involving Alcohols 418
14.10 Polymeric Alcohols 418
14.11 Structural Characteristics of Phenols 419
14.12 Nomenclature for Phenols 419
14.13 Physical and Chemical Properties of Phenols 420
14.14 Occurrence of and Uses for Phenols 421 14.15 Structural Characteristics of Ethers 422 14.16 Nomenclature for Ethers 423
14.17 Isomerism for Ethers 426 14.18 Physical and Chemical Properties of Ethers 427 14.19 Cyclic Ethers 428
14.20 Sulfur Analogs of Alcohols 429 14.21 Sulfur Analogs of Ethers 431 CHEMICAL CONNECTIONS
Menthol: A Useful Naturally Occurring Terpene Alcohol 408 Ethers as General Anesthetics 425
Marijuana: The Most Commonly Used Illicit Drug 429 Garlic and Onions: Odiferous Medicinal Plants 432 CHEMISTRY AT A GLANCE Alcohols, Thiols, Ethers, and Thioethers 433
Chapter 15 Aldehydes and Ketones 442
15.1 The Carbonyl Group 442 15.2 Compounds Containing a Carbonyl Group 443 15.3 The Aldehyde and Ketone Functional Groups 444 15.4 Nomenclature for Aldehydes 445
15.5 Nomenclature for Ketones 447 15.6 Isomerism for Aldehydes and Ketones 449 15.7 Selected Common Aldehydes and Ketones 450 15.8 Physical Properties of Aldehydes and Ketones 451 15.9 Preparation of Aldehydes and Ketones 453 15.10 Oxidation and Reduction of Aldehydes and Ketones 455
15.11 Reaction of Aldehydes and Ketones with Alcohols 458
CHEMISTRY AT A GLANCE Summary of Chemical Reactions Involving Aldehydes and Ketones 462
15.12 Formaldehyde-Based Polymers 463 15.13 Sulfur-Containing Carbonyl Groups 464 CHEMICAL CONNECTIONS
Lachrymatory Aldehydes and Ketones 449 Melanin: A Hair and Skin Pigment 452 Diabetes, Aldehyde Oxidation, and Glucose Testing 456
Chapter 16 Carboxylic Acids, Esters, and
Other Acid Derivatives 473
16.1 Structure of Carboxylic Acids and Their Derivatives 473
16.2 IUPAC Nomenclature for Carboxylic Acids 474 16.3 Common Names for Carboxylic Acids 476 16.4 Polyfunctional Carboxylic Acids 479 16.5 Metabolic Carboxylic Acids 482 16.6 Physical Properties of Carboxylic Acids 483 16.7 Preparation of Carboxylic Acids 483 16.8 Acidity of Carboxylic Acids 484 16.9 Carboxylic Acid Salts 484
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Trang 1216.10 Structure of Esters 487
16.11 Preparation of Esters 487
CHEMISTRY AT A GLANCE Summary of the “H Versus R”
Relationship for Pairs of Hydrocarbon Derivatives 488
16.12 Nomenclature for Esters 489
16.13 Selected Common Esters 491
16.14 Isomerism for Carboxylic Acids and Esters 493
16.15 Physical Properties of Esters 495
16.16 Chemical Reactions of Esters 495
16.17 Sulfur Analogs of Esters 497
CHEMISTRY AT A GLANCE Summary of Chemical Reactions
Involving Carboxylic Acids and Esters 498 16.18 Polyesters 499
16.19 Acid Chlorides and Acid Anhydrides 500
16.20 Esters and Anhydrides of Inorganic Acids 503
Nitroglycerin: An Inorganic Triester 505
Chapter 17 Amines and Amides 514
17.1 Bonding Characteristics of Nitrogen Atoms in Organic
Compounds 514 17.2 Structure and Classifi cation of Amines 515
17.3 Nomenclature for Amines 516
17.4 Isomerism for Amines 518
17.5 Physical Properties of Amines 519
17.6 Basicity of Amines 519
17.7 Amine Salts 521
17.8 Preparation of Amines and Quaternary Ammonium
Salts 523 17.9 Heterocyclic Amines 525
17.10 Selected Biochemically Important Amines 526
17.11 Alkaloids 529
17.12 Structure and Classifi cation of Amides 532
17.13 Nomenclature for Amides 533
17.14 Selected Amides and Their Uses 535
17.15 Physical Properties of Amides 536
17.16 Preparation of Amides 537
17.17 Hydrolysis of Amides 540
17.18 Polyamides and Polyurethanes 542
CHEMISTRY AT A GLANCE Summary of Chemical Reactions
Involving Amines and Amides 543 CHEMICAL CONNECTIONS
Caffeine: The Most Widely Used Central Nervous System Stimulant 526
Nicotine Addiction: A Widespread Example of Drug Dependence 527
Alkaloids Present in Chocolate 531 Acetaminophen: A Substituted Amide 538
PA RT I I I B I O LO G I CA L C H E M I ST RY
Chapter 18 Carbohydrates 555
18.1 Biochemistry—An Overview 555 18.2 Occurrence and Functions of Carbohydrates 556 18.3 Classifi cation of Carbohydrates 557
18.4 Chirality: Handedness in Molecules 557 18.5 Stereoisomerism: Enantiomers and Diastereomers 560
18.6 Designating Handedness Using Fischer Projection Formulas 561
CHEMISTRY AT A GLANCE Constitutional Isomers and Stereoisomers 566
18.7 Properties of Enantiomers 566 18.8 Classifi cation of Monosaccharides 569 18.9 Biochemically Important Monosaccharides 570 18.10 Cyclic Forms of Monosaccharides 574
18.11 Haworth Projection Formulas 576 18.12 Reactions of Monosaccharides 577 18.13 Disaccharides 582
CHEMISTRY AT A GLANCE “Sugar Terminology” Associated with Monosaccharides and Their Derivatives 583 18.14 General Characteristics of Polysaccharides 587 18.15 Storage Polysaccharides 591
18.16 Structural Polysaccharides 593 CHEMISTRY AT A GLANCE Types of Glycosidic Linkages for Common Glucose-Containing Di- and
Polysaccharides 595 18.17 Acidic Polysaccharides 595 18.18 Glycolipids and Glycoproteins: Cell Recognition 596 18.19 Dietary Considerations and Carbohydrates 597 CHEMICAL CONNECTIONS
Blood Types and Monosaccharides 580 Lactose Intolerance and Galactosemia 585
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Trang 13Changing Sugar Patterns: Decreased Sucrose, Increased
Fructose 588
Artifi cial Sweeteners 590
“Good and Bad Carbs”: The Glycemic Index 597
Chapter 19 Lipids 608
19.1 Structure and Classifi cation of Lipids 608
19.2 Types of Fatty Acids 609
19.3 Physical Properties of Fatty Acids 613
19.4 Energy-Storage Lipids: Triacylglycerols 614
19.5 Dietary Considerations and Triacylglycerols 618
19.6 Chemical Reactions of Triacylglycerols 621
CHEMISTRY AT A GLANCE Classifi cation Schemes for Fatty
Acid Residues Present in Triacylglycerols 628
19.7 Membrane Lipids: Phospholipids 629
19.8 Membrane Lipids: Sphingoglycolipids 634
CHEMISTRY AT A GLANCE Terminology for and Structural
Relationships Among Various Types of
Fatty-Acid-Containing Lipids 634
19.9 Membrane Lipids: Cholesterol 635
19.10 Cell Membranes 637
19.11 Emulsifi cation Lipids: Bile Acids 640
19.12 Messenger Lipids: Steroid Hormones 641
19.13 Messenger Lipids: Eicosanoids 644
19.14 Protective-Coating Lipids: Biological Waxes 646
CHEMISTRY AT A GLANCE Types of Lipids in Terms of How
They Function 648
CHEMICAL CONNECTIONS
The Fat Content of Tree Nuts and Peanuts 620
Artifi cial Fat Substitutes 624
The Cleansing Action of Soap 625
Trans Fatty Acids and Blood Cholesterol Levels 626
Steroid Drugs in Sports 644
The Mode of Action for Anti-Infl ammatory Drugs 646
Chapter 20 Proteins 655
20.1 Characteristics of Proteins 655
20.2 Amino Acids: The Building Blocks for Proteins 656
20.3 Chirality and Amino Acids 658
20.4 Acid–Base Properties of Amino Acids 659
20.5 Cysteine: A Chemically Unique Amino Acid 663
20.6 Peptides 663
20.7 Biochemically Important Small Peptides 667
20.8 General Structural Characteristics of Proteins 668
20.9 Primary Structure of Proteins 670
20.10 Secondary Structure of Proteins 671
20.11 Tertiary Structure of Proteins 674
20.12 Quaternary Structure of Proteins 677
20.13 Protein Classifi cation Based on Shape 679
20.14 Protein Classifi cation Based on Function 682
CHEMISTRY AT A GLANCE Protein Structure 678
21.1 General Characteristics of Enzymes 698 21.2 Enzyme Structure 699
21.3 Nomenclature and Classifi cation of Enzymes 699 21.4 Models of Enzyme Action 704
21.5 Enzyme Specifi city 705 21.6 Factors That Affect Enzyme Activity 706 CHEMISTRY AT A GLANCE Enzyme Activity 709 21.7 Enzyme Inhibition 710
CHEMISTRY AT A GLANCE Enzyme Inhibition 712 21.8 Regulation of Enzyme Activity 713
21.9 Antibiotics That Inhibit Enzyme Activity 715 21.10 Medical Uses of Enzymes 718
21.11 General Characteristics of Vitamins 718 21.12 Water-Soluble Vitamins 721
21.13 Fat-Soluble Vitamins 725 CHEMICAL CONNECTIONS
H pylori and Stomach Ulcers 707 Enzymatic Browning: Discoloration of Fruits and Vegetables 708
Heart Attacks and Enzyme Analysis 719
xii Contents
Chapter 22 Nucleic Acids 734
22.1 Types of Nucleic Acids 734 22.2 Nucleotides: Building Blocks of Nucleic Acids 735 22.3 Primary Nucleic Acid Structure 738
CHEMISTRY AT A GLANCE Nucleic Acid Structure 741 22.4 The DNA Double Helix 741
22.5 Replication of DNA Molecules 745
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Trang 1422.6 Overview of Protein Synthesis 747
22.7 Ribonucleic Acids 747
CHEMISTRY AT A GLANCE DNA Replication 748
22.8 Transcription: RNA Synthesis 749
22.9 The Genetic Code 753
22.10 Anticodons and tRNA Molecules 756
22.11 Translation: Protein Synthesis 758
22.12 Mutations 763
22.13 Nucleic Acids and Viruses 763
CHEMISTRY AT A GLANCE Protein Synthesis: Transcription
and Translation 764 22.14 Recombinant DNA and Genetic Engineering 765
22.15 The Polymerase Chain Reaction 768
23.2 Metabolism and Cell Structure 779
23.3 Important Intermediate Compounds in Metabolic
Pathways 781 23.4 High-Energy Phosphate Compounds 786
23.5 An Overview of Biochemical Energy
Production 788 23.6 The Citric Acid Cycle 788
CHEMISTRY AT A GLANCE Simplifi ed Summary of the Four
Stages of Biochemical Energy Production 790 CHEMISTRY AT A GLANCE Summary of the Reactions of
the Citric Acid Cycle 794 23.7 The Electron Transport Chain 794
CHEMISTRY AT A GLANCE Summary of the Flow of
Electrons Through the Four Complexes of the Electron Transport Chain 799
23.8 Oxidative Phosphorylation 800
CHEMISTRY AT A GLANCE Summary of the Common
Metabolic Pathway 802 23.9 ATP Production for the Common Metabolic
Pathway 802 23.10 The Importance of ATP 804
23.11 Non-ETC Oxygen-Consuming Reactions 804
CHEMICAL CONNECTIONS
Cyanide Poisoning 801 Brown Fat, Newborn Babies, and Hibernating Animals 803 Flavonoids: An Important Class of Dietary Antioxidants 805
24.5 Glycogen Synthesis and Degradation 828 24.6 Gluconeogenesis 830
24.7 Terminology for Glucose Metabolic Pathways 832 24.8 The Pentose Phosphate Pathway 833
CHEMISTRY AT A GLANCE Glucose Metabolism 835 24.9 Hormonal Control of Carbohydrate Metabolism 835 CHEMICAL CONNECTIONS
Lactate Accumulation 825 Diabetes Mellitus 836
Chapter 25 Lipid Metabolism 842
25.1 Digestion and Absorption of Lipids 842 25.2 Triacylglycerol Storage and Mobilization 845 25.3 Glycerol Metabolism 846
25.4 Oxidation of Fatty Acids 846 25.5 ATP Production from Fatty Acid Oxidation 851 25.6 Ketone Bodies 854
25.7 Biosynthesis of Fatty Acids: Lipogenesis 858 25.8 Relationships Between Lipogenesis and Citric Acid Cycle Intermediates 864
25.9 Biosynthesis of Cholesterol 864 CHEMISTRY AT A GLANCE Interrelationships Between Carbohydrate and Lipid Metabolism 868 25.10 Relationships Between Lipid and Carbohydrate Metabolism 869
CHEMICAL CONNECTIONS High-Intensity Versus Low-Intensity Workouts 853 Statins: Drugs That Lower Plasma Levels of Cholesterol 867
Chapter 26 Protein Metabolism 875
26.1 Protein Digestion and Absorption 875 26.2 Amino Acid Utilization 877
26.3 Transamination and Oxidative Deamination 878 26.4 The Urea Cycle 883
26.5 Amino Acid Carbon Skeletons 888 26.6 Amino Acid Biosynthesis 891 26.7 Hemoglobin Catabolism 892 CHEMISTRY AT A GLANCE Interrelationships Among Carbohydrate, Lipid, and Protein Metabolism 895 26.8 Interrelationships Among Metabolic Pathways 896 CHEMICAL CONNECTIONS
The Chemical Composition of Urine 889 Arginine, Citrulline, and the Chemical Messenger Nitric Oxide 889 Answers to Selected Exercises A-1
Photo Credits A-26 Index/Glossary A-27
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Preface
The positive responses of instructors and students who used the previous four
edi-tions of this text have been gratifying—and have lead to the new fi fth edition that you hold in your hands This new edition represents a renewed commitment to the goals I initially set out to meet when writing the fi rst edition These goals have not changed with the passage of time My initial and still ongoing goals are to write a text in which
䊏 The needs are simultaneously met for the many students in the fi elds of nursing, allied health, biological sciences, agricultural sciences, food sciences, and public health who are required to take such a course
䊏 The development of chemical topics always starts out at ground level The students who will use this text often have little or no background in chemistry and hence approach the course with a good deal of trepidation This “ground level” approach addresses this situation
䊏 The amount and level of mathematics is purposefully restricted Clearly, some ical principles cannot be divorced entirely from mathematics and, when this is the case, appropriate mathematical coverage is included
chem-䊏 The early chapters focus on fundamental chemical principles and the later chapters, built on these principles, develop the concepts and applications central to the fi elds of organic chemistry and biochemistry
FOCUS ON BIOCHEMISTRY Most students taking this course have a greater interest in the biochemistry portion of the course than the preceding two parts But biochemistry, of course, cannot be understood without a knowledge of the fundamentals of organic chem-istry, and understanding organic chemistry in turn depends on knowing the key concepts
of general chemistry Thus, in writing this text, I essentially started from the back and worked forward I began by determining what topics would be considered in the biochem-istry chapters and then tailored the organic and then general sections to support that pres-entation Users of the previous editions confi rm that this approach ensures an effi cient but thorough coverage of the principles needed to understand biochemistry
EMPHASIS ON VISUAL SUPPORT I believe strongly in visual reinforcement of key cepts in a textbook; thus, this book uses art and photos wherever possible to teach key concepts Artwork is used to make connections and highlight what is important for the student to know Reaction equations use color to emphasize the portions of a molecule that undergo change Colors are likewise assigned to things like valence shells and classes
con-of compounds to help students follow trends Computer-generated, three-dimensional lecular models accompany many discussions in the organic and biochemistry sections of the text Color photographs show applications of chemistry to help make concepts real and more readily remembered
mo-Visual summary features, called Chemistry at a Glance, pull together material from
several sections of a chapter to help students see the larger picture For example, Chapter
3 features a Chemistry at a Glance on the shell–subshell–orbital interrelationships;
Chapter 10 presents buffer solutions; Chapter 13 includes IUPAC nomenclature for
al-kanes, alkenes, and alkynes; and Chapter 22 summarizes DNA replication The Chemistry
at a Glance feature serves both as an overview for the student reading the material for the
fi rst time and as a review tool for the student preparing for exams Given the popularity of
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Trang 16the Chemistry at a Glance summaries in the previous editions, several new ones have
been added and several existing ones have been updated or expanded New topics selected
for Chemistry at a Glance boxes include
Acid–base defi nitions
Structural representations for alkanes
Structural characteristics and naming of alcohols, thiols, ethers, and thioethers
Structural components of nucleic acids
COMMITMENT TO STUDENT LEARNING In addition to the study help Chemistry at a Glance offers, the text is built on a strong foundation of learning aids designed to help
students master the course material
Problem-solving pedagogy Because problem solving is often diffi cult for students
in this course to master, I have taken special care to provide support to help students
build their skills Within the chapters, worked-out Examples follow the explanation
of many concepts These examples walk students through the thought processes volved in problem solving, carefully outlining all the steps involved Each is immedi-
in-ately followed by a Practice Exercise, to reinforce the information just presented.
Diversity of worked-out Examples The number of worked-out Examples has been
dramatically increased in this new edition, with most of the increase in the istry chapters of the text Worked-out Examples are a standard feature in the general chemistry portions of all textbooks for this market This relates primarily to the mathematical nature of many general chemistry topics In most texts, including ear-lier editions of this text, fewer worked-out Examples appear in the organic chemistry chapters and still fewer (almost none) in the biochemistry portion because of the mathematical demands decrease This new edition changes that perspective Thirty-two new worked-out Examples are found within the biochemistry scope of the text With the increasing detail that now accompanies biochemistry discussions about the human body, such Examples are warranted and can be very helpful for students
biochem- Chemical Connections In every chapter Chemical Connections show chemistry as
it appears in everyday life These boxes focus on topics that are relevant to students’ future careers in the health and environmental fi elds and on those that are important
for informed citizens to understand Many of the health-related Chemical
Connections have been updated to include the latest research fi ndings, and include
new boxes on metallic elements and the human body, iron (the most abundant tion element in the human body), carbon monoxide toxicity and the human body, the chemistry of nicotine addiction, and changing sugar consumption patterns (decreased sucrose, increased fructose)
transi- Margin notes Liberally distributed throughout the text, margin notes provide tips
for remembering and distinguishing between concepts, highlight links across ters, and describe interesting historical background information
chap- Defi ned terms All defi nitions are highlighted in the text when they are fi rst
pre-sented, using boldface and italic type Each defi ned term appears as a complete tence; students are never forced to deduce a defi nition from context In addition, the
sen-defi nitions of all terms appear in the combined Index/Glossary found at the end of
the text A major emphasis in this new edition has been “refi nements” in the defi ned terms arena All defi ned terms were reexamined to see if they could be stated with greater clarity The result was a “rewording” of many defi ned terms
Review aids Several review aids appear at the ends of the chapters Concepts to
Remember and Key Reactions and Equations provide concise review of the material
presented in the chapter A Key Terms Review lists all the key terms in the chapter
alphabetically and cross-references the section of the chapter in which they appear These aids help students prepare for exams
End-of-chapter problems An extensive set of end-of-chapter problems complements
the worked examples within the chapters Each end-of-chapter problem set is divided
into two sections: Exercises and Problems and Additional Problems The Exercises
Preface xv
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Trang 17and Problems are organized by topic and paired, with each pair testing similar
material and the answer to the odd-numbered member of the pair at the back of
the book These problems always involve only a single concept The Additional
Problems involve more than one concept and are more diffi cult than the Exercises
and Problems
A new feature of this edition is the placement of 67 new “visual concept” problems in the general chemistry problem sets This new problem type, which is integrated throughout the problem sets, is designed to facilitate learning through the use of molecular models, pictorial representations of chemical systems, graphs, and other visual portrayals
Multiple-choice practice tests Practice tests at the end of each chapter act as a
cu-mulative overview and self-study tool
CONTENT CHANGES Coverage of a number of topics has been expanded in this edition The two driving forces in expanded coverage considerations were (1) the requests of users and reviewers of the previous editions and (2) my desire to incorporate new research fi ndings, particularly in the area of biochemistry, into the text Topics with expanded coverage include
Percent composition by mass
Colloidal dispersion and suspensions
Equivalent and milliequivalent concentration units
Nuclear stability
Nuclear medicine
Alkane–base polymers
Cyclic esters (lactones)
Polyester type polymers
Acyl transfer reactions
Amine salts
Polyamide and polyurethane type polymers
Protein isoelectric points
Protein classifi cation by molecular shape and by function
Regulation of enzyme activity
Ribosome structure
Post-translational phase of protein synthesis
Recombinant DNA technology
Glycogenolysis
Ketogeneis
Lipogenesis
SUPPORTING MATERIALS
Supporting instructor materials are available to qualifi ed adopters Please consult your
local Cengage Learning, Brooks/Cole representative for details Visit www.cengage.com/
chemistry/stoker to
See samples of materials
Request a desk copy
Locate your local representative
Download electronic fi les of the Lab Manual Instructor’s Resource Manual and other
helpful materials for instructors and students
POWERLECTURE WITH DIPLOMA TESTING AND JOININ TM INSTRUCTOR’S DVD
PowerLecture (ISBN-10: 0-495-83160-3; ISBN-13: 978-0-495-83160-0) is a one-stop digital library and presentation tool that includes
xvi Preface
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Trang 18Prepared Microsoft ® PowerPoint ® Lecture Slides that cover all key points from the
text in a convenient format with art and photographs You can enhance the slides with your own materials or with additional interactive video and animations on the DVD for personalized, media-enhanced lectures
Image libraries in PowerPoint and JPEG formats that contain electronic fi les for all
text art, most photographs, and all numbered tables in the text These fi les can be used to create your own transparencies or PowerPoint lectures
JoinIn “clicker” Slides written specifi cally for the use of Chemistry with the classroom
response system of your choice that allows you to seamlessly display student answers
The Complete Solutions Manual (H Stephen Stoker), which contains answers to all
end-of-chapter exercises
Sample chapters from the Study Guide with Solutions to Selected Problems.
The Instructor’s Resource Guide for the textbook and for Experimental Chemistry.
The Test Bank in printable Word and PDF documents, which provide an easy way to
view all questions and answers from Diploma® Testing
Diploma® Testing, which combines a fl exible test-editing program with comprehensive
gradebook functions for easy administration and tracking With Diploma Testing,
instruc-tors can administer tests via print, network server, or the Web Questions can be selected based on their chapter/section, level of diffi culty, question format, algorithmic functional-
ity, topic, learning objective, and fi ve levels of key words With Diploma ® Testing you can
Choose from the 2,500 test items designed to measure the concepts and principles covered in the text
Ensure that each student gets a different version of the problem by selecting from preprogrammed algorithmic questions
Edit or author algorithmic or static questions that integrate into the existing bank, becoming part of the question database for future use
Choose problems designated as single-skill (easy), multi-skill (medium), and challenging and multi-skill (hard)
Customize tests to assess the specifi c content from the text
Create several forms of the same test where questions and answers are scrambled
OWL: ONLINE WEB-BASED LEARNING OWL is authored
by Roberta Day, Beatrice Botch, and David Gross of the University of Massachusetts, Amherst; William Vining of the State University of New York at Oneonta; and Susan Young of Hartwick College:
OWL Instant Access (two semesters): ISBN-10: 0-495-11105-8; 495-11105-4
ISBN-13:978-0-Instant Access to OWL e-Book (two semesters): ISBN-10: 0-495-83162-X; ISBN-13: 978-0-495-83162-4
Developed at the University of Massachusetts, Amherst, and class tested by tens of thousands of chemistry students, OWL is a fully customizable and fl exible web-based learn-ing system OWL supports mastery learning and offers numerical, chemical, and contextual parameterization to produce thousands of problems correlated to this text The OWL system also features a database of simulations, tutorials, and exercises, as well as end-of-chapter problems from the text With OWL, you get the most widely used online learning system available for chemistry with unsurpassed reliability and dedicated training and support The optional e-Book in OWL includes the complete electronic version of the text,
fully integrated and linked to OWL homework problems Most e-books in OWL are active and offer highlighting, notetaking, and bookmarking features that can all be saved
inter-To view an OWL demo and for more information, visit www.cengage.com/owl or contact
your Cengage Learning, Brooks/Cole representative
LAB MANUAL INSTRUCTORS RESOURCE MANUAL Available on PowerLecture DVD
and on the instructor companion site, this guide, by G Lynn Carlson, Senior Lecturer
Preface xvii
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Trang 19Emeritus University of Wisconsin-Parkside, includes additional information related to the experiments in the Lab Manual Additional safety notes, references, and web resources enhance the experience of the Lab for both the instructor and the students.
CENGAGE LEARNING CUSTOM SOLUTIONS This allows you to develop personalized text solutions to meet your course needs Match your learning materials to your syllabus and create the perfect learning solution—your customized text will contain the same thought-provoking, scientifi cally sound content, superior authorship, and stunning art that you’ve come to expect from Cengage Learning, Brooks/Cole texts, yet in a more fl exible
format Visit www.cengage.com/custom.com to start building your book today.
Visit the student website at www.cengage.com/chemistry/stoker to see samples of select
student supplements Students can purchase any Cengage Learning product at your local
college store or at our preferred online store www.ichapters.com.
STUDENT COMPANION WEBSITE Accessible from www.cengage.com/chemistry/
stoker, this site provides online study tools including practice tests, fl ashcards, and
Careers in Chemistry
OWL FOR GENERAL, ORGANIC, AND BIOLOGICAL
CHEMISTRY See the above description in the instructor support materials section
STUDY GUIDE WITH SOLUTIONS TO SELECTED PROBLEMS By Danny V White of American River College and Joanne A White, this useful resource (ISBN: 0-547-16808-X; ISBN 13: 978-0-547-16808-1) will reinforce your skills with activities and practice problems for each chapter After completing the end-of-chapter exercises, you’ll be able
to check your answers for the odd-numbered questions
LAB MANUAL The Lab Manual (ISBN-10: 0-547-16793-8; ISBN-13:
978-0-547-16793-0) to accompany this textbook, by G Lynn Carlson, Senior Lecturer Emeritus University of Wisconsin-Parkside, includes 42 experiments that were selected to match the topics in your textbook Each experiment has an introduction, a procedure, a page of pre-lab exercises about the concepts the lab illustrates, and a report form Some have a scenario that places the experiment in a real-world context In addition, each experiment has a link to a set of references and on-line resources that might help you succeed with the experiment
E SSENTIAL A LGEBRA FOR C HEMISTRY S TUDENTS, SECOND EDITION This short book
by David W Ball, Cleveland State University (ISBN-10: 0-495-01327-7; ISBN-13 495-01327-3) is intended for students who lack confi dence or competency in their essen-tial mathematics skills necessary to survive in general chemistry Each chapter focuses on
978-0-a specifi c type of skill 978-0-and h978-0-as worked-out ex978-0-amples to show how these skills tr978-0-ansl978-0-ate to chemical problem solving It includes references to OWL, our web-based tutorial pro-gram that offers students access to online algebra skills exercises
S URVIVAL G UIDE FOR G ENERAL C HEMISTRY WITH M ATH R EVIEW AND P ROFICIENCY
Q UESTIONS, SECOND EDITION Intended to help you practice for exams, this survival guide by Charles H Atwood, University of Georgia (ISBN-10: 0-495-38751-7; ISBN-13 978-0-495-38751-0) shows you how to solve diffi cult problems by dissecting them into manageable chunks The guide includes three levels of profi ciency questions—A, B, and minimal—to quickly build confi dence as you master the knowledge you need to succeed
in your course
xviii Preface
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Trang 20For the Laboratory
CENGAGE LEARNING, BROOKS/COLE LAB MANUALS We offer a variety of printed manuals to meet all your general chemistry laboratory needs Instructors can visit the
chemistry site at www.cengage.com/chemistry for a full listing and description of these
laboratory manuals and laboratory notebooks All Cengage Learning lab manuals can be customized for your specifi c needs
SIGNATURE LABS FOR THE CUSTOMIZED LABORATORY Signature Labs combines the resources of Brooks/Cole, CER, and OuterNet Publishing to provide you unparalleled service in creating your ideal customized lab program Select the experiments and art-work you need from our collection of content and imagery to fi nd the perfect labs to
match your course Visit www.signaturelabs.com or contact your Cengage Learning
rep-resentative for more information
ACKNOWLEDGMENTS
I would like to gratefully acknowledge the helpful comments of reviewers
Teresa Brown, Rochester Community and Technical College; Karen Frindell, Santa Rosa Junior College; Irene Gerow, East Carolina University; Kevin Gratton, Johnson County Community College; Sherell Hickman, Brevard Community College; Martina Kaledin, Kennesaw State University; Allen W Leung, Rio Hondo Community College; Michael J Muhitch, Rochester University; Anthony Oertling, Eastern Washington University; James
R Paulson, University of Wisconsin—Oshkosh; Paul Sampson, Kent State University; Heather Sklenicka, Rochester Community and Technical College; Bobby Stanton, University of Georgia; Richard B Triplett, Des Moines Area Community College; David
A Tramontozzi, Macomb Community College; Paolos Yohannes, Georgia Perimeter College.
Jennifer Adamski, Old Dominion University; M Reza Asdjodi, University of Wisconsin— Eau Claire; Irene Gerow, East Carolina University; Ernest Kho, University of Hawaii at Hilo; Larry L Land, University of Florida; Michael Myers, California State University— Long Beach; H A Peoples, Las Positas College; Shashi Rishi, Greenville Technical College; Steven M Socol, McHenry County College.
Special thanks go to Richard B Triplett, Des Moines Area Community College; David
Vanderlinden, Des Moines Area Community College; Barry Ganong, Mansfi eld
University; and Michelle B Moore, Weber State University for their help in ensuring this book’s accuracy Thanks to Richard Gurney, Simmons College, for his contribution of
PowerPoint Lecture Outline content
I also give special thanks to the people at Brooks/Cole, Cengage Learning, who guided the revision through various stages of development and production: Charles Hartford, Publisher, Chemistry; Senior Development Editor, Rebecca Berardy Schwartz; Andrea Cava, Project Editor; Naomi Kornhauser, Photo Researcher; and Stephanie VanCamp, Associate Editor
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Trang 22EMPHASIS ON VISUAL SUPPORT
Visual reinforcement is integral to the approach of this textbook Art and photos are used whenever possible to teach key concepts.
Throughout the text, an exciting
photo program helps students see
the everyday applications of the chemistry they are learning
Artwork is used to make
connections between macroscale and microscale phenomena
O O O
⫹ O Sulfuric acid
(H 2 SO4)
S
HO BO OH B O O
O
⫹ CH 3 OH H 2 O
Methyl ester of sulfuric acid
CH 3
B OOH O O O
⫹ O Nitric acid
(HNO 3 )
OH O B O
O
A N
N CH 3
Methyl ester of nitric acid
HO OBO CH 3
OOH
OH O O
⫹ O
(H 3 PO 4 )
⫹ CH 3 H 2 O
A P A
Phosphoric acid
HO OH O B O O
P OH
Methyl ester of phosphoric acid
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Reaction equations use color to emphasize the
portions of a molecule that undergo change
Color is often used to highlight
dif-ferences between related structures
In the same manner that carboxylic acids are acidic (Section 16.8), phosphoric acid, diphosphoric acid, and triphosphoric acid are also acidic The phosphoric acids are, however, polyprotic rather than monoprotic acids The hydrogen atom in each of the
—OH groups possesses acidic properties All three phosphoric acids undergo esterifi tion reactions with alcohols, producing species such as
ca-A Triphosphate monoester
O B
O O O O P
O O B
A
O P
OH OH
O R
and
A Diphosphate monoester
OH O B
O O O O P O
O BA
Carbohydrate Metabolism
Chapter Outline
24.1 Digestion and Absorption of Carbohydrates 811 24.2 Glycolysis 813 24.3 Fates of Pyruvate 822 24.4 ATP Production for the Complete Oxidation of Glucose 826 24.5 Glycogen Synthesis and Degradation 828 24.6 Gluconeogenesis 830 24.7 Terminology for Glucose Metabolic Pathways 832 24.8 The Pentose Phosphate Pathway 833
CHEMISTRY AT A GLANCE:Glucose Metabolism 835 24.9 Hormonal Control of Carbohydrate Metabolism 835
CHEMICAL CONNECTIONS
Lactate Accumulation 825 Diabetes Mellitus 836
In this chapter we explore the relationship between carbohydrate metabolism and energy production in cells The molecule glucose is the focal point of carbohydrate circulatory system and, after being absorbed by a cell, can be either oxidized to yield totally oxidized to CO 2 and H 2 O However, in the absence of oxygen, glucose is only partially oxidized to lactic acid Besides supplying energy needs, glucose and other six- carbon sugars can be converted into a variety of different sugars (C 3 , C 4 , C 5 , and C 7 ) needed for biosynthesis Some of the oxidative steps in carbohydrate metabolism also produce NADH and NADPH, sources of reductive power in cells.
ion
Figure 4.4 (a, b) A two-dimensional cross-section and a three-dimensional view of sodium chloride (NaCl), an ionic solid Both views show an alternating array of positive and negative ions (c) Sodium chloride crystals.
Trang 23CHEMISTRY AT GLANCE
Chemistry at a Glance diagrams demonstrate interrelationships among concepts.
Chemistry at a Glance
pulls together material
from a group of sections
or a whole chapter to
help students see the
larger picture through a
visual summary
xxii
Summary of Colligative Property Terminology
Addition of a nonvolatile the vapor pressure of the solution LOWER than that
of the solvent alone.
The pressure required to stop the net flow of water across a semipermeable membrane separating solutions of differing composition.
Osmolarity = molarity × i, wherei = number of particles
from the dissociation of one formula unit of solute.
OSMOTIC PRESSURE
OSMOLARITY
Solution with an osmotic pressure HIGHER than that
FREEZING-POINT DEPRESSION
The physical properties of a solution that depend only on the
in a given quantity of solute, not
on the chemical identity of the particles.
COLLIGATIVE PROPERTIES
OF SOLUTIONS
Addition of a nonvolatile solute to a solvent makes the boiling point of the solution HIGHER than that of the solvent alone.
BOILING-POINT ELEVATION
Solution with an osmotic pressure EQUAL to that in cells.
Has no effect on cell size.
Solution with an osmotic pressure LOWER than that
in cells.
Causes cells to hemolyze (burst).
VAPOR-PRESSURE LOWERING
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Aluminum reacts with iodine to form aluminum iodide.
COMBINATION REACTION
X Y
X + Y
2AlI 3 2Al + 3I 2
Mercury(II) oxide decomposes
to form mercury and oxygen.
Zn +
X + ZnSO 4
Cu +
Silver nitrate reacts with sodium chloride to form silver chloride and sodium nitrate.
DOUBLE-REPLACEMENT REACTION +
Types of Chemical Reactions
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Many Chemistry at a
Glance features have
been revised and several new ones have been added
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Trang 24CONNECTING TO CHEMISTRY
In addition to Chemistry at a Glance, the text is built on a strong foundation of learning aids
designed to help students master the course material.
Looking forward/looking back margin notes show
students the connections
of concepts both in what they've learned previously and in what's to come
1.8 NAMES AND CHEMICAL SYMBOLS OF THE ELEMENTS
Each element has a unique name that, in most cases, was selected by it wide variety of rationales for choosing a name have been applied Some geographical names; germanium is named after the native country of i coverer, and the elements francium and polonium are named after Fran The elements mercury, uranium, and neptunium are all named for p gets its name from the Greek word helios, for “sun,” because it was
spectroscopically in the sun’s corona during an eclipse Some elemen that reflect specific properties of the element or of the compounds Chlorine’s name is derived from the Greek chloros, denoting “greeni
color of chlorine gas Iridium gets its name from the Greek iris, mean
this alludes to the varying colors of the compounds from which it was Abbreviations called chemical symbols also exist for the names of
chemical symbol is a one- or two-letter designation for an element d
element’s name These chemical symbols are used more frequently tha
names Chemical symbols can be written more quickly than the names, a less space A list of the known elements and their chemical symbols is giv The chemical symbols and names of the more frequently encountered elem
in color in this table.
Note that the fi rst letter of a chemical symbol is always capitalized
is not Two-letter chemical symbols are often, but not always, the fi rst tw element’s name.
Eleven elements have chemical symbols that bear no relationship t English-language name In ten of these cases, the symbol is derived name of the element; in the case of the element tungsten, a German name source Most of these elements have been known for hundreds of years
t th ti h L ti th l f i ti t El t h
Learning the chemical symbols of the more common elements is an im- portant key to success in studying chemistry Knowledge of chemical symbols is essential for writing chemical formulas (Section 1.10) and chemical equations (Section 6.6).
V Cr Mn Fe Co Ni Cu Zn Mo
Period 4
Transition Metals
Period 5 Period 6
Iron is the most abundant, from a biochemical standpoint, of these transition metals; zinc is the second most abundant.
Most of the body’s iron is found as a component of the teins hemoglobin and myoglobin, where it functions in the transport and storage of oxygen Hemoglobin is the oxygen car- rier in red blood cells, and myoglobin stores oxygen in muscle cells Iron-defi cient blood has less oxygen-carrying capacity Energy defi ciency—tiredness and apathy—is one of the symp- toms of iron defi ciency.
pro-Iron defi ciency is a worldwide problem Millions of people are unknowingly defi cient Even in the United States and Canada, about 20% of women and 3% of men have this prob- ing fatigue, weakness, apathy, and headaches.
Inadequate intake of iron, either from malnutrition or from high consumption of the wrong foods, is the usual cause of iron defi ciency In the Western world, the cause is often displace- ment of iron-rich foods by foods high in sugar and fat.
About 80% of the iron in the body is in the blood, so iron losses are greatest whenever blood is lost Blood loss from great as a man’s Also, women usually consume less food than men do These two factors—lower intake and higher loss—
cause iron defi ciency to be likelier in women than in men The adult males and older women For women of childbearing age, the RDA is 18 mg This amount is necessary to replace menstrual loss and to provide the extra iron needed during pregnancy.
Iron defi ciency may also be caused by poor absorption of ingested iron A normal, healthy person absorbs about 2%–10%
40% of the iron in meat, fi sh, and poultry is bound into oglobin Heme iron is much more readily absorbed (23%) than nonheme iron (2%–10%) (See the accompanying charts.) Cooking utensils can enhance the amount of iron delivered
mole-by the diet The iron content of 100 g of spaghetti sauce mered in a glass dish is 3 mg, but it is 87 mg when the sauce is takes to scramble eggs, their iron content can be tripled by cooking them in an iron pan.
sim-Iron: The Most Abundant Transition Element
in the Human Body
60%
Nonheme iron
40%
Heme iron
Iron content of food derived from animal flesh
Nonheme iron
Iron content of food derived from plants
90%
Nonheme iron
10%
Heme iron
Total dietary iron intake (daily average)
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Margin notes summarize
key information, give tips for remembering or distinguishing between similar ideas, and provide additional details and links between concepts
1.3 PROPERTIES OF MATTER
Various kinds of matter are distinguished from each other by their properties A property
is a distinguishing characteristic of a substance that is used in its identifi cation and description Each substance has a unique set of properties that distinguishes it from all
other substances Properties of matter are of two general types: physical and chemical.
Aphysical property is a characteristic of a substance that can be observed without
changing the basic identity of the substance Common physical properties include color,
odor, physical state (solid, liquid, or gas), melting point, boiling point, and hardness.
During the process of determining a physical property, the physical appearance of a substance may change, but the substance’s identity does not For example, it is impossible
to measure the melting point of a solid without changing the solid into a liquid Although the liquid’s appearance is much different from that of the solid, the substance is still the same; its chemical identity has not changed Hence melting point is a physical property.
Achemical property is a characteristic of a substance that describes the way the
substance undergoes or resists change to form a new substance For example, copper objects
Chemical properties describe the ability of a substance to form new substances, either by reaction with other substances or by decomposi- tion Physical properties are proper- ties associated with a substance’s physical existence They can be de- termined without reference to any other substance, and determining them causes no change in the iden- tity of the substance.
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Chemical Connections boxes
show chemistry as it appears
in everyday life Topics are relevant to students' future careers in the health and environmental fi elds and are important for informed citizens to understand
Trang 25PROBLEM-SOLVING PEDAGOGY
Learning how to solve problems is a key concept in chemistry, as it is in life The Examples
support students as they build these skills.
The value of R is the same for all gases under normally encountered conditions of
tem-perature, pressure, and volume.
If three of the four variables in the ideal gas law equation are known, then the fourth can be calculated using the equation Example 7.4 illustrates the use of the ideal gas law.
Solution
This problem deals with only one set of conditions, so the ideal gas equation is applicable
Three of the four variables in the ideal gas equation (P, n, and T ) are given, and the fourth (V) is to be calculated.
Because the pressure is given in atmospheres and the volume unit is liters, the R value 0.0821
is valid Substituting known numerical values into the equation gives
V5
11.52 moles2 3 a0.0821 atm? L
mole ? Kb1338 K20.992 atm
Note that all the parts of the ideal gas constant unit cancel except for one, the volume part Doing the arithmetic yields the volume of CO.
V5 a1.523 0.0821 3 338
0.992 b L 5 42.5 L
A sample of clean air is the most common example of a mixture of gases that do not react with one another.
7.8 DALTON’S LAW OF PARTIAL PRESSURES
In a mixture of gases that do not react with one another, each type of molecule moves around in the container as though the other kinds were not there This type of behavior is possible because a gas is mostly empty space, and attractions between molecules in the gaseous state are negligible at most temperatures and pressures Each gas in the mixture occupies the entire volume of the container; that is, it distributes itself uniformly through- out the container The molecules of each type strike the walls of the container as frequently and with the same energy as though they were the only gas in the mixture Consequently, the pressure exerted by each gas in a mixture is the same as it would be if the gas were alone
in the same container under the same conditions.
The English scientist John Dalton (Figure 7.13) was the fi rst to notice the independent behavior of gases in mixtures In 1803, he published a summary statement concerning this
behavior that is now known as Dalton’s law of partial pressures Dalton’s law of partial
Figure 7.13 John Dalton (1766–1844) throughout his life had a particular interest in the study of weather From
“weather” he turned his attention to the nature of the atmosphere and then to the study of gases in general.
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Within the chapters worked-out
Examples follow the explanation
of many concepts These
exam-ples walk students through the
thought process involved in
problem solving, carefully
outlining all the steps involved
Examples are immediately
Trang 26COMPREHENSIVE END-OF-CHAPTER REVIEW AND PRACTICE
End-of-chapter review material and an extensive set of problems geared for different types of
learners provide ample opportunity for mastery.
Concepts to Remember and Key Reactions and Equations
provide concise review of the material presented in the chapter, helping students prepare for exam
New visual problem types are integrated throughout
these problem sets and are designed to facilitate learning through the use of molecular models, pictorial representations of chemical systems, graphs, and other visual portrayals
Extensive and varied Exercises and
Problems at the end of each chapter
are organized by topic and paired
These problems always involve only a single concept Answers to selected problems can be found at the back of
or from the sharing of electrons between atoms (covalent bond) (Section 4.1).
Valence electrons. Valence electrons, for representative elements, are the electrons in the outermost electron shell, which is the shell with the highest shell number These electrons are particularly important in determining the bonding characteristics of a given atom (Section 4.2).
Octet rule. In compound formation, atoms of representative elements lose, gain, or share electrons in such a way that their electron confi gu- rations become identical to those of the noble gas nearest them in the periodic table (Section 4.3).
Ionic compounds. Ionic compounds commonly involve a metal atom and a nonmetal atom Metal atoms lose one or more electrons, producing positive ions Nonmetal atoms acquire the electrons lost
by the metal atoms, producing negative ions The oppositely charged ions attract one another, creating ionic bonds (Section 4.4).
Charge magnitude for ions. Metal atoms containing one, two, or three valence electrons tend to lose such electrons, producing ions of
1, 2, or 3 charge, respectively Nonmetal atoms containing fi ve, six, or seven valence electrons tend to gain electrons, producing ions
Chemical formulas for ionic compounds. The ratio in which tive and negative ions combine is the ratio that causes the total amount
posi-of positive and negative charges to add up to zero (Section 4.7).
Structure of ionic compounds. Ionic solids consist of positive and negative ions arranged in such a way that each ion is surrounded by ions of the opposite charge (Section 4.8).
Binary ionic compound nomenclature. Binary ionic compounds are named by giving the full name of the metallic element fi rst, followed
by a separate word containing the stem of the nonmetallic element
name and the suffi x -ide A Roman numeral specifying ionic charge is
appended to the name of the metallic element if it is a metal that exhibits variable ionic charge (Section 4.9).
Polyatomic ions. A polyatomic ion is a group of covalently bonded atoms that has acquired a charge through the loss or gain of electrons
Polyatomic ions are very stable entities that generally maintain their identity during chemical reactions (Section 4.10).
EY R E A C T I O N S A N D EQ U AT I O N S
k
1 Number of valence electrons for representative elements (Section 4.2)
2 Charges on metallic monatomic ions (Section 4.5)
3 Charges on nonmetallic monatomic ions (Section 4.5)
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EX E ER RCI SE Sa a n dP RO O L EM M S
The members of each pair of problems in this section test similar material.
Types of Chemical Bonds (Section 4.1)
the mechanism by which they form.
4.2 Contrast the two general types of chemical compounds in terms
of their general physical properties.
Valence Electrons (Section 4.2)
elec-tron confi gurations have?
4.4 How many valence electrons do atoms with the following
elec-tron confi gurations have?
electrons present for each of the following representative elements.
4.6 Give the periodic-table group number and the number of valence
electrons present for each of the following representative elements.
following representative elements.
a Period 2 element with four valence electrons
b Period 2 element with seven valence electrons
c Period 3 element with two valence electrons
d Period 3 element with fi ve valence electrons
4.8 Write the complete electron confi guration for each of the
following representative elements.
a Period 2 element with one valence electron
b Period 2 element with six valence electrons
c Period 3 element with seven valence electrons
d Period 3 element with three valence electrons
Lewis Symbols for Atoms (Section 4.2)
4.10 Draw Lewis symbols for atoms of each of the following elements.
element Determine each element’s identity.
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4.54 In general terms, how many formula units are present in a
crys-tal of an ionic compound?
with red spheres denoting positive ions and blue spheres ing negative ions.
Which of these drawings could be used as a representation for each of the following ionic compounds?
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Trang 27END-OF-CHAPTER REVIEW AND PRACTICE
(continued)
xxvi
ADD DITIONAL P PR R RO OBLLEMS
4.87 Fill in the blanks to complete the following table.
Positive Negative Chemical Ion Ion Formula Name Magnesium hydroxide BaBr 2
Zn 2 NO 3
Iron(III) chlorate PbO 2
4.88 Fill in the blanks to complete the following table.
Chemical Number of Number of Number of Net Symbol Protons Neutrons Electrons Charge
a A sodium ion with ten electrons
b A fl uorine ion with ten electrons
c A sulfur ion with two fewer protons than electrons
d A calcium ion with two more protons than electrons
Additional Problems
involve more than one concept and are more diffi cult than the Exercises and Problems
The Multiple-Choice
Practice Test at the
end each chapter provides a cumulative review
4.90 Write the formula of the ionic compound that could form from
the elements X and Z if
a X has two valence electrons and Z has seven valence electrons
b X has one valence electron and Z has six valence electrons
c X has three valence electrons and Z has fi ve valence electrons
d X has six valence electrons and Z has two valence electrons
4.91 Identify the Period 3 element that most commonly produces
each of the following ions.
a X 2 b X 2 c X 3 d X 3
4.92 Indicate whether each of the following compounds contains (1)
only monatomic ions, (2) only polyatomic ions, (3) both atomic and polyatomic ions, or (4) no ions.
a CaF 2 b NaNO 3 c NH 4 CN d AlP
4.93 Write chemical formulas (symbol and charge) for both kinds of
ions present in each of the following compounds.
a KCl b CaS c BeF 2 d Al 2 S 3
4.94 Give the chemical formula for, and the name of the compound
formed from, each of the following pairs of ions.
a Na and N 3 b K and NO 3
c Mg 2 and O 2 d NH 4 and PO 4
4.95 Name each compound in the following pairs of binary ionic
compounds.
a SnCl 4 and SnCl 2 b FeS and Fe 2 S 3
c Cu 3 N and Cu 3 N 2 d NiI 2 and NiI 3
4.96 In which of the following pairs of binary ionic compounds do both
members of the pair contain positive ions with the same charge?
a Co 2 O 3 and CoCl 3 b Cu 2 O and CuO
c K 2 O and Al 2 O 3 d MgS and NaI
4.97 Name each compound in the following pairs of
ion-containing compounds.
a CuNO 3 and Cu(NO 3 ) 2 b Pb 3 (PO 4 ) 2 and Pb 3 (PO 4 ) 4
c Mn(CN) 3 and Mn(CN) 2 d Co(ClO 3 ) 2 and Co(ClO 3 ) 3
4.98 Write chemical formulas for the following compounds.
a Sodium sulfi de b Sodium sulfate
c Sodium sulfi te d Sodium thiosulfate
4.99 For which of the following elements is the listed number of
valence electrons correct?
a Mg (2 valence electrons) b N (3 valence electrons)
c F (1 valence electron) d S (2 valence electrons)
4.100 Which of the following is an incorrect statement about the
number of electrons lost or gained by a representative element during ion formation?
a The number usually does not exceed three.
b The number is governed by the octet rule.
c The number is related to the position of the element in the periodic table.
d The number is the same as the number of valence electrons present.
4.101 Which of the following is a correct statement concerning the
mechanism for ionic bond formation?
a Electrons are transferred from nonmetallic atoms to lic atoms.
b Protons are transferred from the nuclei of metallic atoms to the nuclei of nonmetallic atoms.
c Suffi cient electrons are transferred to form ions of equal but opposite charge.
d Electron loss is always equal to electron gain.
4.102 In which of the following pairings is the chemical formula not
consistent with the ions shown?
4.104 In which of the following pairs of ionic compounds do both
members of the pair contain positive ions with a 1 charge?
a KCl and CaO b Na 3 N and Li 2 S
c AlCl 3 and MgF 2 d BaI 2 and BeBr 2
4.105 The correct chemical formula for the compound aluminum
nitride is
a AlN b AlN 2 c Al 2 N 3 d Al 3 N 2
4.106 In which of the following pairs of metals are both members of
the pair variable-charge metals?
a Na and Al b Au and Ag
c Cu and Zn d Fe and Ni
4.107 In which of the following pairs of polyatomic ions do both
members of the pair have the same charge?
a ammonium and phosphate
b sulfate and nitrate
c cyanide and hydroxide
d hydrogen carbonate and carbonate
4.108 Which of the following ionic compounds contains 4 atoms per
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Trang 30Numerous physical and chemical changes in matter occur during a volcanic eruption.
Chapter Outline
1.1 Chemistry: The Study of Matter 1
1.2 Physical States of Matter 2
1.3 Properties of Matter 2
1.4 Changes in Matter 4
CHEMISTRY AT A GLANCE: Use of the Terms
Physical and Chemical 5
1.5 Pure Substances and Mixtures 6
1.6 Elements and Compounds 7
CHEMISTRY AT A GLANCE: Classes
of Matter 8
1.7 Discovery and Abundance of
the Elements 9 1.8 Names and Chemical Symbols of
the Elements 11 1.9 Atoms and Molecules 12
1.10 Chemical Formulas 15
CHEMICAL CONNECTIONS
“Good” Versus “Bad” Properties for
a Chemical Substance 3 Elemental Composition of the Human Body 11
In this chapter we address the question, “What exactly is chemistry about?” In
addi-tion, we consider common terminology associated with the fi eld of chemistry Much
of this terminology is introduced in the context of the ways in which matter is
classi-fi ed Like all other sciences, chemistry has its own speciclassi-fi c language It is necessary to restrict the meanings of some words so that all chemists (and those who study chemis-try) can understand a given description of a chemical phenomenon in the same way
CHEMISTRY: THE STUDY OF MATTER
Chemistry is the fi eld of study concerned with the characteristics, composition, and
transformations of matter What is matter? Matter is anything that has mass and occupies
space The term mass refers to the amount of matter present in a sample.
Matter includes all things—both living and nonliving—that can be seen (such as plants, soil, and rocks), as well as things that cannot be seen (such as air and bacteria) Various forms of energy such as heat, light, and electricity are not considered to be matter However, chemists must be concerned with energy as well as with matter because nearly all changes that matter undergoes involve the release or absorption of energy
The scope of chemistry is extremely broad, and it touches every aspect of our lives
An iron gate rusting, a chocolate cake baking, the diagnosis and treatment of a heart attack, the propulsion of a jet airliner, and the digesting of food all fall within the realm
of chemistry The key to understanding such diverse processes is an understanding of the fundamental nature of matter, which is what we now consider
1
1 1 1
Basic Concepts About Matter
1
The universe is composed entirely of
matter and energy.
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Trang 311.2 PHYSICAL STATES OF MATTER
Three physical states exist for matter: solid, liquid, and gas The classifi cation of a given matter sample in terms of physical state is based on whether its shape and volume are defi -nite or indefi nite
Solid is the physical state characterized by a defi nite shape and a defi nite volume A
dollar coin has the same shape and volume whether it is placed in a large container or on
a table top (Figure 1.1a) For solids in powdered or granulated forms, such as sugar or salt,
a quantity of the solid takes the shape of the portion of the container it occupies, but each individual particle has a defi nite shape and defi nite volume Liquid is the physical state
characterized by an indefi nite shape and a defi nite volume A liquid always takes the shape
of its container to the extent that it fi lls the container (Figure 1.1b) Gas is the physical
state characterized by an indefi nite shape and an indefi nite volume A gas always completely
fi lls its container, adopting both the container’s volume and its shape (Figure 1.1c)
The state of matter observed for a particular substance depends on its temperature, the surrounding pressure, and the strength of the forces holding its structural particles together At the temperatures and pressures normally encountered on Earth, water is one
of the few substances found in all three of its physical states: solid ice, liquid water, and gaseous steam (Figure 1.2) Under laboratory conditions, states other than those com-monly observed can be attained for almost all substances Oxygen, which is nearly always thought of as a gas, becomes a liquid at ⫺183°C and a solid at ⫺218°C The metal iron
is a gas at extremely high temperatures (above 3000°C)
1.3 PROPERTIES OF MATTER
Various kinds of matter are distinguished from each other by their properties A property
is a distinguishing characteristic of a substance that is used in its identifi cation and description Each substance has a unique set of properties that distinguishes it from all
other substances Properties of matter are of two general types: physical and chemical
A physical property is a characteristic of a substance that can be observed without
changing the basic identity of the substance Common physical properties include color,
odor, physical state (solid, liquid, or gas), melting point, boiling point, and hardness
During the process of determining a physical property, the physical appearance of a substance may change, but the substance’s identity does not For example, it is impossible
to measure the melting point of a solid without changing the solid into a liquid Although the liquid’s appearance is much different from that of the solid, the substance is still the same; its chemical identity has not changed Hence melting point is a physical property
A chemical property is a characteristic of a substance that describes the way the
substance undergoes or resists change to form a new substance For example, copper objects
shape and a defi nite volume (b) A
liq-uid has an indefi nite shape— it takes
the shape of its container— and a defi
-nite volume (c) A gas has an indefi -nite
shape and an indefi nite volume— it
assumes the shape and volume of its
container.
the solid, liquid, and vapor (gaseous)
forms simultaneously, as shown here
at Yellowstone National Park.
Chemical properties describe the
ability of a substance to form new
substances, either by reaction with
other substances or by
decomposi-tion Physical properties are
proper-ties associated with a substance’s
physical existence They can be
de-termined without reference to any
other substance, and determining
them causes no change in the
iden-tity of the substance.
The volume of a sample of matter is
a measure of the amount of space
occupied by the sample.
2 Chapter 1 Basic Concepts About Matter
Trang 32chem-of a second substance is not an absolute requirement Sometimes the presence chem-of energy (usually heat or light) can trigger the change called decomposition That hydrogen per-
oxide, in the presence of either heat or light, decomposes into the substances water and oxygen is a chemical property of hydrogen peroxide
When we specify chemical properties, we usually give conditions such as perature and pressure because they infl uence the interactions between substances For example, the gases oxygen and hydrogen are unreactive toward each other at room temperature, but they interact explosively at a temperature of several hundred degrees
a Iron metal rusts in an atmosphere of moist air.
b Mercury metal is a liquid at room temperature.
c Nickel metal dissolves in acid to produce a light green solution.
d Potassium metal has a melting point of 63°C.
It is important not to judge the signifi cance or usefulness of a
chemical substance on the basis of just one or two of the many
chemical and physical properties it exhibits Possession of a
“bad” property, such as toxicity or a strong noxious odor, does
not mean that a chemical substance has nothing to contribute to
the betterment of human society
A case in point is the substance carbon monoxide Everyone knows that it is a gaseous air pollutant present in automobile ex-
haust and cigarette smoke and that it is toxic to human beings
For this reason, some people automatically label carbon
monox-ide a “bad” substance, a substance we do not need or want
Indeed, carbon monoxide is toxic to human beings It impairs man health by reducing the oxygen-carrying capacity of the blood
hu-Carbon monoxide does this by interacting with the hemoglobin in
red blood cells in a way that prevents the hemoglobin from
distribut-ing oxygen throughout the body Someone who dies from carbon
monoxide poisoning actually dies from lack of oxygen
The fact that carbon monoxide is colorless, odorless, and tasteless is very signifi cant Because of these properties, carbon
monoxide gives no warning of its initial presence There are
several other common air pollutants that are more toxic than
carbon monoxide However, they have properties that give
warning of their presence and hence they are not considered as
“dangerous” as carbon monoxide
Despite its toxicity, carbon monoxide plays an important role
in the maintenance of the high standard of living we now enjoy Its contribution lies in the fi eld of iron metallurgy and the produc-tion of steel The isolation of iron from iron ores, necessary for the production of steel, involves a series of high-temperature reac-tions, carried out in a blast furnace, in which the iron content of molten iron ores reacts with carbon monoxide These reactions re-lease the iron from its ores The carbon monoxide needed in steel making is obtained by reacting coke (a product derived by heating coal to a high temperature without air being present) with oxygen.The industrial consumption of the metal iron, both in the United States and worldwide, is approximately ten times greater than that of all other metals combined Steel production ac-counts for nearly all of this demand for iron Without steel, our standard of living would drop dramatically, and carbon monox-ide is necessary for the production of steel
Is carbon monoxide a “good” or a “bad” chemical substance? The answer to this question depends on the context in which the carbon monoxide is encountered In terms of air pollution, it is a
“bad” substance In terms of steel making, it is a “good” stance A similar “good–bad” dichotomy exists for almost every chemical substance
sub-“Good” Versus “Bad” Properties for a Chemical Substance
(continued)
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Trang 331.4 CHANGES IN MATTER
Changes in matter are common and familiar occurrences Changes take place when food is digested, paper is burned, and a pencil is sharpened Like properties of matter, changes in matter are classifi ed into two categories: physical and chemical
A physical change is a process in which a substance changes its physical
appear-ance but not its chemical composition A new substappear-ance is never formed as a result of
a physical change
A change in physical state is the most common type of physical change Melting, freezing, evaporation, and condensation are all changes of state In any of these processes, the composition of the substance undergoing change remains the same even though its physical state and appearance change The melting of ice does not produce a new substance; the substance is water both before and after the change Similarly, the steam produced from boiling water is still water
A chemical change is a process in which a substance undergoes a change in
chemical composition Chemical changes always involve conversion of the material or
materials under consideration into one or more new substances, each of which has erties and composition distinctly different from those of the original materials Consider, for example, the rusting of iron objects left exposed to moist air (Figure 1.4) The red-dish brown substance (the rust) that forms is a new substance with chemical properties that are obviously different from those of the original iron
prop-Answers: a physical property; b chemical property; c physical property; d chemical property
Practice Exercise 1.1
Classify each of the following properties for selected metals as a physical property or a chemical property.
a Titanium metal can be drawn into thin wires.
b Silver metal shows no sign of reaction when placed in hydrochloric acid.
c Copper metal possesses a reddish brown color.
d Beryllium metal, when inhaled in a fi nely divided form, can produce serious lung disease.
Solution
a Chemical property The interaction of iron metal with moist air produces a new
substance (rust)
b Physical property Visually determining the physical state of a substance does not
produce a new substance
c Chemical property A change in color indicates the formation of a new substance.
d Physical property Measuring the melting point of a substance does not change the
Physysysicicalaalal a a a aaaaaandndnnddChhemememmmicicicccalaalaalalaalall i iiiin n
Deescssccrirririribibbibbibbibngngnngngnngngg CChaangnngngggesesesess
Complete each of the following statements about changes in matter by placing the word
physical or chemical in the blank.
a The fashioning of a piece of wood into a round table leg involves a change
b The vigorous reaction of potassium metal with water to produce hydrogen gas is a
change
c Straightening a bent piece of iron with a hammer is an example of a change
d The ignition and burning of a match involve a change
Statue of Liberty results from the
reac-tion of the copper skin of the statue
with the components of air That
cop-per will react with the components of
air is a chemical property of copper.
4 Chapter 1 Basic Concepts About Matter
change, bright steel girders become
rusty when exposed to moist air.
Trang 341.4 Changes in Matter 5
Answers: a chemical; b physical; c chemical; d physical
Practice Exercise 1.2
Complete each of the following statements about changes in matter by placing the word
physical or chemical in the blank.
a The destruction of a newspaper through burning involves a change
b The grating of a piece of cheese is a change
c The heating of a blue powdered material to produce a white glassy substance and a gas
is a change
d The crushing of ice cubes to make ice chips is a change
Chemists study the nature of changes in matter to learn how to bring about ble changes and prevent undesirable ones The control of chemical change has been a major factor in attainment of the modern standard of living now enjoyed by most people
favora-in the developed world The many plastics, synthetic fi bers, and prescription drugs now
in common use are derived via controlled chemical change
The Chemistry at a Glance feature below reviews the ways in which the terms
physical and chemical are used to describe the properties of substances and the changes
Solution
a Physical The table leg is still wood No new substances have been formed.
b Chemical A new substance, hydrogen, is produced.
c Physical The piece of iron is still a piece of iron.
d Chemical New gaseous substances, as well as heat and light, are produced as the match burns.
Use of the Terms Physical and Chemical
PHYSICAL
Physical Properties
This term conveys the idea that the composition (chemical identity) of a substance DOES NOT CHANGE
Color and shape Solid, liquid, or gas Boiling point, melting point
Properties observable without changing composition
Physical Changes
Changes observable without changing composition Change in physical state (melting, boiling, freezing, etc.)
Change in state of subdivision with no change in physical state (pulverizing a solid)
CHEMICAL
Chemical Properties
This term conveys the idea that the composition (chemical identity) of a substance DOES CHANGE
Properties that describe how a substance changes (or resists change) to form a new substance
Chemical Changes
Changes in which one or more new substances are formed
Decomposition Reaction with another substance
Flammability (or flammability) Decomposition at a high temperature (or lack of decomposition) Reaction with chlorine (or lack of reaction with chlorine)
non-Physical changes need not involve a
change of state Pulverizing an
aspi-rin tablet into a powder and cutting a
piece of adhesive tape into small
pieces are physical changes that
in-volve only the solid state.
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Trang 35that substances undergo Note that the term physical, used as a modifi er, always conveys
the idea that the composition (chemical identity) of a substance did not change, and that the term chemical, used as a modifi er, always conveys the idea that the composition of
a substance did change
1.5 PURE SUBSTANCES AND MIXTURES
In addition to its classifi cation by physical state (Section 1.2), matter can also be classifi ed in terms of its chemical composition as a pure substance or as a mixture A pure substance is
a single kind of matter that cannot be separated into other kinds of matter by any physical means All samples of a pure substance contain only that substance and nothing else Pure
water is water and nothing else Pure sucrose (table sugar) contains only that substance and nothing else
A pure substance always has a defi nite and constant composition This invariant composition dictates that the properties of a pure substance are always the same under
a given set of conditions Collectively, these defi nite and constant physical and chemical properties constitute the means by which we identify the pure substance
A mixture is a physical combination of two or more pure substances in which each
substance retains its own chemical identity Components of a mixture retain their identity
because they are physically mixed rather than chemically combined Consider a mixture
of small rock salt crystals and ordinary sand Mixing these two substances changes ther the salt nor the sand in any way The larger, colorless salt particles are easily dis-tinguished from the smaller, light-gray sand granules
nei-One characteristic of any mixture is that its components can be separated by using physical means In our salt–sand mixture, the larger salt crystals could be—though very tediously—“picked out” from the sand A somewhat easier separation method would be
to dissolve the salt in water, which would leave the undissolved sand behind The salt could then be recovered by evaporation of the water Figure 1.5a shows a heterogeneous mixture of potassium dichromate (orange crystals) and iron fi lings A magnet can be used
to separate the components of this mixture (Figure 1.5b)
Another characteristic of a mixture is variable composition Numerous different salt–
sand mixtures, with compositions ranging from a slightly salty sand mixture to a slightly sandy salt mixture, could be made by varying the amounts of the two components
Mixtures are subclassifi ed as heterogeneous or homogeneous This subclassifi cation
is based on visual recognition of the mixture’s components A heterogeneous mixture
is a mixture that contains visibly different phases (parts), each of which has different properties A nonuniform appearance is a characteristic of all heterogeneous mixtures
Examples include chocolate chip cookies and blueberry muffi ns Naturally occurring heterogeneous mixtures include rocks, soils, and wood
A homogeneous mixture is a mixture that contains only one visibly distinct phase
(part), which has uniform properties throughout The components present in a
homogene-ous mixture cannot be visually distinguished A sugar–water mixture in which all of the
Substance is a general term used to
denote any variety of matter Pure
substance is a specifi c term that is
applied to matter that contains only
a single substance.
All samples of a pure substance, no
matter what their source, have the
same properties under the same
conditions.
Most naturally occurring samples of
matter are mixtures Gold and
dia-mond are two of the few naturally
occurring pure substances Despite
their scarcity in nature, numerous
pure substances are known They are
obtained from natural mixtures by
using various types of separation
techniques or are synthesized in the
laboratory from naturally occurring
materials.
and a mixture consisting of potassium
dichromate (the orange crystals) and
iron fi lings (b) The magnet can be
used to separate the iron fi lings from
the potassium dichromate.
6 Chapter 1 Basic Concepts About Matter
Trang 361.6 Elements and Compounds 7
sugar has dissolved has an appearance similar to that of pure water Air is a homogeneous mixture of gases; motor oil and gasoline are multicomponent homogeneous mixtures of liquids; and metal alloys such as 14-karat gold (a mixture of copper and gold) are exam-ples of homogeneous mixtures of solids The homogeneity present in solid-state metallic alloys is achieved by mixing the metals while they are in the molten state
Figure 1.6 summarizes what we have learned thus far about various classifi cations
of matter
1.6 ELEMENTS AND COMPOUNDS
Chemists have isolated and characterized an estimated 9 million pure substances A very small number of these pure substances, 117 to be exact, are different from all of the others They are elements All of the rest, the remaining millions, are compounds What distin-guishes an element from a compound?
An element is a pure substance that cannot be broken down into simpler pure
substances by chemical means such as a chemical reaction, an electric current, heat, or
a beam of light The metals gold, silver, and copper are all elements.
A compound is a pure substance that can be broken down into two or more simpler
pure substances by chemical means Water is a compound By means of an electric
cur-rent, water can be broken down into the gases hydrogen and oxygen, both of which are elements The ultimate breakdown products for any compound are elements A compound’s properties are always different from those of its component elements, because the elements are chemically rather than physically combined in the compound (Figure 1.7)
One visible phase
HOMOGENEOUS MIXTURE
Two or more visible phases
HETEROGENEOUS MIXTURE
Only one substance present
PURE SUBSTANCE
Physical combination of two or more substances
MIXTURE
Anything that has mass and occupies space
MATTER
classes: pure substances and mixtures
Mixtures, in turn, may be homogeneous
or heterogeneous.
Cannot be broken down into simpler substances by chemical or physical means
ELEMENT
Can be broken down into constituent elements by chemical, but not physical, means
COMPOUND
Only one substance present
PURE SUBSTANCE
either an element or a compound.
Both elements and compounds are
pure substances.
The defi nition for the term element
that is given here will do for now
After considering the concept of
atomic number (Section 3.2), we
will give a more precise defi nition.
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Trang 37Classes of Matter
Can be broken down into constituent elements by chemical, but not physical, means
Compounds
Cannot be broken down
into simpler substances
Building blocks for all
other types of matter
117 elements known
Chemical combination
of two or more elements Have definite, constant, elemental composition
Definite and constant composition Properties always the same under the same conditions
Two or more visible phases
Heterogeneous Mixtures
One visible phase
Physical combination
of two or more substances
Mixtures
Same properties throughout Different properties
in different phases
Composition can vary Properties can vary with composition
Homogeneous Mixtures
Consider two boxes with the following contents: the fi rst contains 10 locks and 10 keys that
fi t the locks; the second contains 10 locks with each lock’s key inserted into the cylinder
Which box has contents that would be an analogy for a mixture and which box has contents that would be an analogy for a compound?
Solution
The box containing the locks with their keys inserted in the cylinder represents the pound Two objects withdrawn from this box will always be the same; each will be a lock with its associated key Each item in the box has the same “composition.”
com-The box containing separated locks and keys represents the mixture Two objects drawn from this box need not be the same; results could be two locks, two keys, or a lock and
with-a key All items in the box do not hwith-ave the swith-ame “composition.”
Dfffffferereerrrene ceccecee B BBBetettwewweweeneeneenn aaMi
M
MiMi
Mxtxxtxtxturuurururuurrrre eanannd da aCoCCoompmmpmppououoououuundndnd
Even though two or more elements are obtained from decomposition of compounds, compounds are not mixtures Why is this so? Remember, substances can be combined either physically or chemically Physical combination of substances produces a mixture
Chemical combination of substances produces a compound, a substance in which bining entities are bound together No such binding occurs during physical combination
com-Example 1.3, which involves two comparisons involving locks and their keys, nicely illustrates the difference between compounds and mixtures
The Chemistry at a Glance feature above summarizes what we have learned thus far about the subdivisions of matter called pure substances, elements, compounds, and mixtures
Every known compound is made up
of some combination of two or more
of the 117 known elements In any
given compound, the elements are
combined chemically in fi xed
pro-portions by mass.
8 Chapter 1 Basic Concepts About Matter
Trang 381.7 Discovery and Abundance of the Elements 9
Figure 1.8 summarizes the thought processes a chemist goes through in classifying a sample of matter as a heterogeneous mixture, a homogeneous mixture, an element, or a compound This fi gure is based on the following three questions about a sample of matter:
1 Does the sample of matter have the same properties throughout?
2 Are two or more different substances present?
3 Can the pure substance be broken down into simpler substances?
1.7 DISCOVERY AND ABUNDANCE OF THE ELEMENTS
The discovery and isolation of the 117 known elements, the building blocks for all matter, have taken place over a period of several centuries Most of the discoveries have occurred since 1700, the 1800s being the most active period
Eighty-eight of the 117 elements occur naturally, and 29 have been synthesized in the laboratory by bombarding samples of naturally occurring elements with small parti-cles Figure 1.9 shows samples of selected naturally occurring elements The synthetic (laboratory-produced) elements are all unstable (radioactive) and usually revert quickly back to naturally occurring elements (see Section 11.5)
The naturally occurring elements are not evenly distributed on Earth and in the universe What is startling is the nonuniformity of the distribution A small number of elements account for the majority of elemental particles (atoms) (An atom is the small-est particle of an element that can exist; see Section 1.9.)
There are three major property
dis-tinctions between compounds and
mixtures.
1 Compounds have properties
distinctly different from those
of the substances that combined
to form the compound The components of mixtures retain their individual properties.
2 Compounds have a defi nite
composition Mixtures have a variable composition.
3 Physical methods are suffi cient
to separate the components of a mixture The components of a compound cannot be separated
by physical methods; chemical methods are required.
Homogeneous mixture
Yes No
Are two or more different substances present?
Pure substance (in one physical state)
Heterogeneous
Heterogeneous mixture
Yes
No No
Yes No
Yes
Homogeneous
Does the sample of matter have the same properties throughout?
Can the pure substance be broken down into simpler substances?
Are two or more different substances present?
Pure substance (in two or more physical states)
classi-fying matter into various categories.
A student who attended a university
in the year 1700 would have been
taught that 13 elements existed In
1750 he or she would have learned
about 16 elements, in 1800 about 34,
in 1850 about 59, in 1900 about 82,
and in 1950 about 98 Today’s total
of 117 elements was reached in 2006.
Answers: fi rst box, mixture; second box, compound
Practice Exercise 1.3
Consider two boxes with the following contents: the fi rst contains 30 bolts and 30 nuts that
fi t the bolts; the second contains the same number of bolts and nuts with the difference that each bolt has a nut screwed on it Which box has contents that would be an analogy for a mixture and which box has contents that would be an analogy for a compound?
Trang 39Studies of the radiation emitted by stars enable scientists to estimate the elemental composition of the universe (Figure 1.10a) Results indicate that two elements, hydrogen and helium, are absolutely dominant All other elements are mere “impurities” when their abundances are compared with those of these two dominant elements In this big picture,
in which Earth is but a tiny microdot, 91% of all elemental particles (atoms) are gen, and nearly all of the remaining 9% are helium
hydro-If we narrow our view to the chemical world of humans—Earth’s crust (its waters, atmosphere, and outer solid surface)—a different perspective emerges Again, two elements dominate, but this time they are oxygen and silicon Figure 1.10b provides information
on elemental abundances for Earth’s crust The numbers given are atom percents—that
is, the percentage of total atoms that are of a given type Note that the eight elements listed (the only elements with atom percents greater than 1%) account for over 98% of total atoms in Earth’s crust Note also the dominance of oxygen and silicon; these two elements account for 80% of the atoms that make up the chemical world of humans
Oxygen, the most abundant element in Earth’s crust, was isolated in pure form for the fi rst time in 1774 by the English chemist and theologian Joseph Priestly (1733–1804)
Discovery years for the other “top fi ve” elements of Earth’s crust are 1824 (silicon), 1827 (aluminum), 1766 (hydrogen), and 1808 (calcium)
appear-ance of selected naturally occurring
elements Center: Sulfur From upper
right, clockwise: Arsenic, iodine,
mag-nesium, bismuth, and mercury.
Any increase in the number of
known elements from 117 will result
from the production of additional
synthetic elements Current chemical
theory strongly suggests that all
nat-urally occurring elements have been
identifi ed The isolation of the last of
the known naturally occurring
ele-ments, rhenium, occurred in 1925.
(in atom percent) in the universe (a)
and in Earth’s crust (b).
10 Chapter 1 Basic Concepts About Matter
Trang 40c HEMICAL
onnections
1.8 Names and Chemical Symbols of the Elements 11
1.8 1.8 NAMES AND CHEMICAL SYMBOLS OF THE ELEMENTS
Each element has a unique name that, in most cases, was selected by its discoverer A wide variety of rationales for choosing a name have been applied Some elements bear geographical names; germanium is named after the native country of its German dis-coverer, and the elements francium and polonium are named after France and Poland The elements mercury, uranium, and neptunium are all named for planets Helium gets its name from the Greek word helios, for “sun,” because it was first observed
spectroscopically in the sun’s corona during an eclipse Some elements carry names that reflect specific properties of the element or of the compounds that contain it Chlorine’s name is derived from the Greek chloros, denoting “greenish-yellow,” the
color of chlorine gas Iridium gets its name from the Greek iris, meaning “rainbow”;
this alludes to the varying colors of the compounds from which it was isolated.Abbreviations called chemical symbols also exist for the names of the elements A
chemical symbol is a one- or two-letter designation for an element derived from the
element’s name These chemical symbols are used more frequently than the elements’
names Chemical symbols can be written more quickly than the names, and they occupy less space A list of the known elements and their chemical symbols is given in Table 1.1 The chemical symbols and names of the more frequently encountered elements are shown
in color in this table
Note that the fi rst letter of a chemical symbol is always capitalized and the second
is not Two-letter chemical symbols are often, but not always, the fi rst two letters of the element’s name
Eleven elements have chemical symbols that bear no relationship to the element’s English-language name In ten of these cases, the symbol is derived from the Latin name of the element; in the case of the element tungsten, a German name is the symbol’s source Most of these elements have been known for hundreds of years and date back
to the time when Latin was the language of scientists Elements whose chemical bols are derived from non-English names are marked with an asterisk in Table 1.1
sym-Learning the chemical symbols of
the more common elements is an
im-portant key to success in studying
chemistry Knowledge of chemical
symbols is essential for writing
chemical formulas (Section 1.10)
and chemical equations (Section 6.6).
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The distribution of elements in the human body and other living
systems is very different from that found in Earth’s crust This
distribution is the result of living systems selectively taking up
matter from their external environment rather than simply
accu-mulating matter representative of their surroundings Food
in-take constitutes the primary selective inin-take process
Only four elements are found in the human body at atom cent levels greater than 1%
per-Hydrogen, carbon, and nitrogen are all much more abundant than in Earth’s crust (Figure 1.10b), and oxygen is signifi cantly less abundant than in Earth’s crust
The dominance of hydrogen and oxygen in the human body refl ects its high water content Hydrogen is over twice as abundant
as oxygen, largely because water contains hydrogen and oxygen
in a 2-to-1 atom ratio
Carbohydrates, fats, and proteins, nutrients required by the man body in large amounts, are all sources of carbon, hydrogen, and oxygen Proteins are the body’s primary nitrogen source
hu-Elemental Composition of the Human Body
Oxygen 25.7%
Hydrogen 60.5%
All others 0.7%
Nitrogen 2.4%
Carbon 10.7%
Water Carbohydrate Fat
Protein
Hydrogen Oxygen Carbon Nitrogen
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